Carbon-Supported Ag Nanoparticle Aerogel for Electrocatalytic Hydrogenation of 5-(Hydroxymethyl)furfural to 2,5-Hexanedione Under Acidic Conditions

Abstract

A growing interest in the electrochemical conversion of biomass-derived compounds is attributed to the extremely high sustainability of this process, which has the potential to generate value-added products and renewable electricity from biowastes. The design and synthesis of a high surface area-interconnected porous network of metal nanomaterials are desirable for their application in the field of catalysis. In this work, the synthesis of the carbon-supported Ag nanoparticle aerogel (Ag–aerogel–CN x ) for electrocatalytic hydrogenation of 5-(hydroxymethyl)­furfural (HMF) is studied. The conversion of HMF to 2,5-hexanedione (HD) via ring opening using ambient pressure and temperature is demonstrated. Here, water is used as the hydrogen source and silver is used as the metal catalyst, which eliminates the use of H2 gas and the conventional method of hydrogenation that uses high pressure and temperature, which makes this reduction process more practical and efficient to produce HD. We investigated the most favorable potential for high Faradic efficiency and provided a plausible reduction path from HMF to HD. The production of HD is strongly dependent on the cathode potential and the nature of the electrolyte. The tuning of the cathodic potential can give high Faradic efficiency and suppress the other undesired byproducts like H2. A high Faradic efficiency of 78% and selectivity of 77% are observed for the conversion of HMF to HD on Ag–aerogel–CN x at −1.1 V versus Ag/AgCl in 0.5 M H2SO4. This direct six-electron reduction of HMF to HD can provide a new route to produce valuable intermediates from biomass.

Linear diketones as next-generation biomass-derived platform molecules: from heterogeneous catalytic synthesis to supply of high-end chemicals

“…4), which consisted of the processes of hydrogenolysis and Clemmensen reduction as well as furan ring-opening. In addition to the work of Choi et al , 52 similar mechanisms have been reported by Barman et al (with carbon-supported Ag nanoparticle aerogel as the electrode) 53 and Sarno et al (with Ag/graphene as the electrode). 97 Although the reported cases on electrocatalytic reduction are still very scarce, this is a highly promising route to replace thermocatalysis.…”

“…9. 53 In addition, linear diketones have also been widely reported for the synthesis of N-substituted pyrroles. These pyrroles are often deemed as indispensable five-membered N-containing heterocyclic backbones for the preparation of many commercial drugs with examples including aloracetam (for Alzheimer's disease), atorvastatin (for cardiovascular disease), etc.…”

“…[47][48][49][50] The biomass-derived linear diketones mentioned in most of the recent studies basically refer to 2,5hexanedione (HD) and 1-hydroxy-2,5-hexanedione (HHD), which has led them to become highly representative linear diketones in the field of biomass conversion. [51][52][53][54][55] As promising novel platform molecules, HD and HHD can be usually obtained via the tandem conversion of C 6 furan compounds, [56][57][58] which are readily produced from real biomass feedstocks and their derived carbohydrates. 59,60 Meanwhile, recent reports have also confirmed that HD and HHD can be chemically transformed to synthesize a range of high-end chemical products for energy, food, pharmaceutical and many other purposes.…”

A mini review of electrocatalytic upgrading of carbohydrate biomass—System, path, and optimization

“…156 For example, a high Faradaic efficiency of 78% and a selectivity of 77% were observed for the conversion of HMF to 2,5-hexanedione on Ag-aerogel-CN x at −1.1 V versus Ag/AgCl in 0.5 mol L −1 H 2 SO 4 . 157 In addition to these, DHMTHF can also be produced through the intermediate of DHMF. Li et al synthesized the use of a bifunctional Pd/VN (VN-3D vanadium nitride) hollow nanosphere electrode for the simultaneous electrocatalytic oxidation and electrocatalytic hydrogenation of HMF at both F I G U R E 10 Reaction pathway of electrocatalytic hydrogenation of 5-HMF.…”

Einstein’s tea leaf paradox induced localized aggregation of nanoparticles and their conversion to gold aerogels

“…Recently, metal aerogels including gold aerogels (GAs) have aroused broad interest in catalysis, adsorption, electrochemistry, biocompatibility devices, sensors, and various other fields (10)(11)(12)(13)(14)(15)(16)(17). Three main routes to the preparation of metal aerogels have been developed previously, including (i) reducing metal compound aerogel (18)(19)(20), (ii) freezing-drying metal nanowire hydrogel (21)(22)(23), and (iii) using self-assemble technology to collect metal NPs (10,(16)(17)(24)(25)(26)(27).…”